If I were to guess, I'd say about... 40% of the residents here practice magic. Of course, a lot of the technology to my eyes looks magical, so I might be biased.
Personally? Alternate universes. But speaking more broadly, many of the magic-users here focus on particular issues or challenges that plagued them at home. There are several magical schools for those with the aptitude, though I don't teach at them because ugh, youths, as well as a variety of covens.